StateContext.h

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#pragma once
 
#include <QtCore/QHash>
#include <QtCore/QString>
#include <QtCore/QVariant>
 
#include <any>
#include <optional>
#include <typeinfo>
 
class StateContext
{
public:
    StateContext() = default;
    ~StateContext() = default;
 
    // -------------------------------------------------------------------------
    // Type-safe API (preferred)
    // -------------------------------------------------------------------------
 
    template<typename T>
    void set(const QString& key, T&& value)
    {
        _data[key] = std::any(std::forward<T>(value));
    }
 
    template<typename T>
    std::optional<T> get(const QString& key) const
    {
        auto it = _data.find(key);
        if (it == _data.end()) {
            return std::nullopt;
        }
 
        try {
            return std::any_cast<T>(it.value());
        } catch (const std::bad_any_cast&) {
            return std::nullopt;
        }
    }
 
    template<typename T>
    T getOr(const QString& key, const T& defaultValue) const
    {
        auto result = get<T>(key);
        return result.value_or(defaultValue);
    }
 
    bool contains(const QString& key) const
    {
        return _data.contains(key);
    }
 
    template<typename T>
    bool containsType(const QString& key) const
    {
        auto it = _data.find(key);
        if (it == _data.end()) {
            return false;
        }
        return it.value().type() == typeid(T);
    }
 
    bool remove(const QString& key)
    {
        return _data.remove(key);
    }
 
    void clear()
    {
        _data.clear();
    }
 
    int count() const
    {
        return _data.count();
    }
 
    QStringList keys() const
    {
        return _data.keys();
    }
 
    // -------------------------------------------------------------------------
    // QVariant API (for QML compatibility)
    // -------------------------------------------------------------------------
 
    void setVariant(const QString& key, const QVariant& value)
    {
        _variantData[key] = value;
    }
 
    QVariant variant(const QString& key) const
    {
        return _variantData.value(key);
    }
 
    bool containsVariant(const QString& key) const
    {
        return _variantData.contains(key);
    }
 
private:
    QHash<QString, std::any> _data;
    QHash<QString, QVariant> _variantData;
};